Dry cleaning involves the use of chemical solvents instead of water to clean the fabric of garments and the like. The solvents typically comprise substantially nonacqueous organic solvents such as trichloroethylene, tetrachloroethylene or naptha, to which special detergents are often added to enhance cleansing. Dirt and grease become dissolved in the solvent as the dirty garments are scrubbed in the rotating drums. Hair, lint, etc. are also picked up by the solvent. After cleansing, the drums are rotated at a higher speed to separate the dirty solvent from the garments. The cleaned garments are then removed from the drum for drying and pressing before return to the customer, while the dirty solvent is collected for recycling.
Purification of such cleaning solvents is typically accomplished by means of filtration and/or distillation. The dirty solvent is first passed through a filter assembly wherein the non-dissolved matter such as lint, hair etc., is separated from the solvent. After filtration, the solvent is also distilled to remove any remaining oil, grease or water therefrom. It will be appreciated that such solvent is volatile material which must be handled with care. Solvent vapors can pose a health hazard upon prolonged exposure without adequate ventilation.
Heretofore, the usual practice has been to discard the filter elements when they became dirty and clogged. It will be appreciated that replacement of such filter elements involves expense in terms of the cost of the filter elements themselves, the labor involved in removing and replacing them, and the down-time of the cleaning system. In addition, such clogged filter elements are usually saturated with solvent which is lost upon replacement. Finally, clogged filter elements saturated with solvent are subject to hazardous waste requirements, which in turn involve additional expense and special handling techniques for disposal. Periodic removal and replacement of the filter elements in a cleaning system thus involves substantial expense.
A need has thus arisen for an improved reclamation apparatus for a dry cleaning system whereby the saturated solvent in the filter element can be periodically extracted to recycle additional solvent, to extend the useful life of the filter elements, to render otherwise hazardous dirty filter elements safe for ordinary disposal, and to reduce down-time of the cleaning system due to filter maintenance.